【Android】从无到有：手把手一步步教你自定义RecyclerView手势监听

转载请注明出处，原文链接：https://blog.csdn.net/u013642500/article/details/80488425

【前言】

1、关于如何构建并使用RecyclerView，请参考：https://blog.csdn.net/u013642500/article/details/80480906

2、本文可以实现 GestureDetector 类的全部手势操作方法，包括 onSingleTapUp、onLongPress、onScroll、onFling、onShowPress、onDown、onDoubleTap、onDoubleTapEvent、onSingleTapConfirmed、onContextClick。

3、手势操作各个方法的含义，请参考：https://blog.csdn.net/u013642500/article/details/80489115

【构造自定义监听器】

1、新建 RecyclerItemClickListener 类，添加 RecyclerView.OnItemTouchListener 接口。

package com.test.myapplication;import android.support.v7.widget.RecyclerView;import android.view.MotionEvent;public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {    @Override    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {        return false;    }    @Override    public void onTouchEvent(RecyclerView rv, MotionEvent e) {    }    @Override    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {    }}

2、写四个全局变量：

    private OnItemClickListener mListener;    private GestureDetector mGestureDetector;    private View childView;    private RecyclerView touchView;

3、重写 onInterceptTouchEvent 方法：

    @Override    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {        touchView = rv;        childView = rv.findChildViewUnder(e.getX(), e.getY());        mGestureDetector.onTouchEvent(e);        return false;    }

4、写一个接口 OnItemClickListener（方法自定义，想写几个几个，看你的需求了）：

    public interface OnItemClickListener {        void onItemClick(View view, int position);        void onLongClick(View view, int position);        void onScroll(View view, int position);    }

5、写构造函数，有两个参数：Context context 和 RecyclerItemClickListener.OnItemClickListener listener：

    public RecyclerItemClickListener(Context context, RecyclerItemClickListener.OnItemClickListener listener){    }

6、在构造函数中，实例化 GestureDetector 类对象：

    public RecyclerItemClickListener(Context context, RecyclerItemClickListener.OnItemClickListener listener){        mListener = listener;        mGestureDetector = new GestureDetector(context,new GestureDetector.SimpleOnGestureListener());    }

7、重写 GestureDetector.SimpleOnGestureListener 类的方法（需要几个写几个）：

        mGestureDetector = new GestureDetector(context,new GestureDetector.SimpleOnGestureListener(){            @Override            public boolean onSingleTapUp(MotionEvent e) {                return super.onSingleTapUp(e);            }            @Override            public void onLongPress(MotionEvent e) {                super.onLongPress(e);            }            @Override            public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {                return super.onScroll(e1, e2, distanceX, distanceY);            }        });

8、自定义接口与手势之间的“绑定”：

        mGestureDetector = new GestureDetector(context,new GestureDetector.SimpleOnGestureListener(){            @Override            public boolean onSingleTapUp(MotionEvent e) {                if (childView != null && mListener != null) {                    mListener.onItemClick(childView, touchView.getChildAdapterPosition(childView));                }                return true;            }            @Override            public void onLongPress(MotionEvent e) {                if (childView != null && mListener != null) {                    mListener.onLongClick(childView, touchView.getChildAdapterPosition(childView));                }            }            @Override            public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {                if (childView != null && mListener != null) {                    mListener.onScroll(childView, touchView.getChildAdapterPosition(childView));                }                return true;            }        });

【使用自定义监听器】

在 MainActivity 中，给 RecyclerView 对象添加 item 触摸监听：

        recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(this, new RecyclerItemClickListener.OnItemClickListener() {            @Override            public void onItemClick(View view, int position) {                Toast.makeText(getApplicationContext(), "点击了第" + position + "项", Toast.LENGTH_SHORT).show();            }            @Override            public void onLongClick(View view, int position) {                Toast.makeText(getApplicationContext(), "长按了第" + position + "项", Toast.LENGTH_SHORT).show();            }            @Override            public void onScroll(View view, int position) {                Toast.makeText(getApplicationContext(), "滑动了", Toast.LENGTH_SHORT).show();            }        }));

【成果】

【源代码】

RecyclerItemClickListener.java：

package com.test.myapplication;import android.content.Context;import android.support.v7.widget.RecyclerView;import android.view.GestureDetector;import android.view.MotionEvent;import android.view.View;public class RecyclerItemClickListener implements RecyclerView.OnItemTouchListener {    private OnItemClickListener mListener;    private GestureDetector mGestureDetector;    private View childView;    private RecyclerView touchView;    public RecyclerItemClickListener(Context context, RecyclerItemClickListener.OnItemClickListener listener){        mListener = listener;        mGestureDetector = new GestureDetector(context,new GestureDetector.SimpleOnGestureListener(){            @Override            public boolean onSingleTapUp(MotionEvent e) {                if (childView != null && mListener != null) {                    mListener.onItemClick(childView, touchView.getChildAdapterPosition(childView));                }                return true;            }            @Override            public void onLongPress(MotionEvent e) {                if (childView != null && mListener != null) {                    mListener.onLongClick(childView, touchView.getChildAdapterPosition(childView));                }            }            @Override            public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {                if (childView != null && mListener != null) {                    mListener.onScroll(childView, touchView.getChildAdapterPosition(childView));                }                return true;            }        });    }    public interface OnItemClickListener {        void onItemClick(View view, int position);        void onLongClick(View view, int position);        void onScroll(View view, int position);    }    @Override    public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {        touchView = rv;        childView = rv.findChildViewUnder(e.getX(), e.getY());        mGestureDetector.onTouchEvent(e);        return false;    }    @Override    public void onTouchEvent(RecyclerView rv, MotionEvent e) {    }    @Override    public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {    }}

MainActivity.java：

package com.test.myapplication;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.support.v7.widget.LinearLayoutManager;import android.support.v7.widget.RecyclerView;import android.view.View;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        List> mList = new ArrayList<>();        List tempList;        tempList = new ArrayList<>();        tempList.add("王一");        tempList.add("18");        mList.add(tempList);        tempList = new ArrayList<>();        tempList.add("赵二");        tempList.add("19");        mList.add(tempList);        tempList = new ArrayList<>();        tempList.add("李三");        tempList.add("16");        mList.add(tempList);        tempList = new ArrayList<>();        tempList.add("孙四");        tempList.add("20");        mList.add(tempList);        // 初始化 RecyclerView        RecyclerView recyclerView = findViewById(R.id.recyclerView);        // 实例化LinearLayoutManager对象        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);        // 设置 RecyclerView 布局为线性布局        recyclerView.setLayoutManager(linearLayoutManager);        // 实例化 Adapter        MyRecyclerView adapter = new MyRecyclerView(this, mList);        // 设置 Adapter        recyclerView.setAdapter(adapter);        recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(this, new RecyclerItemClickListener.OnItemClickListener() {            @Override            public void onItemClick(View view, int position) {                Toast.makeText(getApplicationContext(), "点击了第" + position + "项", Toast.LENGTH_SHORT).show();            }            @Override            public void onLongClick(View view, int position) {                Toast.makeText(getApplicationContext(), "长按了第" + position + "项", Toast.LENGTH_SHORT).show();            }            @Override            public void onScroll(View view, int position) {                Toast.makeText(getApplicationContext(), "滑动了", Toast.LENGTH_SHORT).show();            }        }));    }}

由于本人安卓知识及技术有限，本文如有错误或不足请评论指出，非常感谢！